Ageing and Sexual Selection: How do males and females affect each other's life histories?

My research in the lab of Dr. Russell Bonduriansky aims to explore questions in the evolution of ageing -- How are key life history traits, such as lifespan and reproduction, affected by changes in the environment of an organism? What can these responses tell us about constraints, plasticity and fitness maximization strategies in shaping the process we know as "ageing"?

My main focus in answering these questions is on resource use over the lifetime. One way to think about ageing is as a dwindling pool of resources available to an organism. We can manipulate the size of this resource pool in both development and adulthood by offering varying amounts of nutrients to our animal of interest, a technique commonly known as dietary restriction. Dietary restriction studies allow us to uncover a wealth of information: When resources are scarce, which (non-essential) functions get cut first? If an organism is nutrient-deprived in development, what strategies might it pursue to make the best of the situation? And given that males and females tend to have very different resource needs at various life stages, and vastly different lifetime reproductive optima, how might life history responses to dietary restriction differ between the sexes? Taking it a step further, what happens when another important environmental parameter - the social environment - is altered? How might the sexes respond to a change in the number of available mates and competitors, and how might this response interact with responses to dietary restriction?

I am looking at these questions, among others, by conducting a series of laboratory experiments using a model organism, the neriid fly Telostylinus angusticollis. These flies are long-legged tree dwellers that aggregate, feed, and oviposit on rotting bark. We regularly supplement our lab stocks with flies from the wild, which we collect at a number of field sites in and around Sydney. The photo below, taken by Nori Kawasaki, a previous student in the lab, shows two males fighting for access to an oviposition site. Males that gain dominance at these sites have the opportunity to maximize their reproductive success by mating with the resident females, and so the position is highly coveted and often hard-won.

Photo Credit: Nori Kawasaki

I’ve also done some work during my PhD candidature on the evolution of female behaviour in waterfowl mating systems, human odour preferences and their potential role in mate choice, and (while visiting the lab of Dr. Alexei Maklakov in Uppsala, Sweden) male reproductive ageing in the nematode worm C. remanei. The photo on the right of me holding an orphaned baby African bushbuck was taken last year in Kenya, during a trip to collect a species of fruit fly from a metapopulation with suspected aberrant mitochondrial inheritance.